From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian King Subject: Re: PATCH [3/5] qla2xxx: TCQ fixes Date: Mon, 12 Jul 2004 21:28:20 -0500 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <40F348C4.7070600@us.ibm.com> References: <20040712140558.GA6961@praka.san.rr.com> <1089668486.1799.62.camel@mulgrave> <40F32AAE.5070508@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from e4.ny.us.ibm.com ([32.97.182.104]:45812 "EHLO e4.ny.us.ibm.com") by vger.kernel.org with ESMTP id S261638AbUGMC2s (ORCPT ); Mon, 12 Jul 2004 22:28:48 -0400 In-Reply-To: <40F32AAE.5070508@us.ibm.com> List-Id: linux-scsi@vger.kernel.org To: Mike Christie Cc: James Bottomley , Andrew Vasquez , Linux-SCSI Mailing List , linux-iscsi-devel@lists.sourceforge.net, Krishna Murthy Mike Christie wrote: > James Bottomley wrote: > >> On Mon, 2004-07-12 at 09:05, Andrew Vasquez wrote: >> >>> ChangeSet >>> 1.1867 04/07/12 09:38:28 andrew.vasquez@apc.qlogic.com +2 -0 >>> Correct usage of tag-command-queueing methods: >> >> >> >> I really don't think it is. >> >> For the way the qla2xxx works, the correct tag usage would be to use per >> HBA tags (which were introduced for aic7xxx but never used by them, so I >> haven't actually created the mid-layer API), to populate your queue >> handle field with the tag and to dispense with your outstanding_cmnds[] >> array and use scsi_find_tag() to get back the command from the handle. >> >> Since you'd be the first user of this API, I'd be happy to come up with >> it for a willing victim^Wvolunteer. > > > Depending on the API, we might be able to use it for the linux-iscsi > driver. Today the driver uses scsi_activate_tcq(), but does not uses the > tag numbers. Instead it uses its own initiator task tags values for > session wide identifiers, becuase we need tag values for iscsi ops. For > example if we need to send a ping how should we get a tag from the mid > layer? Or maybe becuase there are some transport specific tag values > should we use someting else or keep it in the driver? ipr is not interested in the tag numbers either, as the adapter microcode generates them. -- Brian King eServer Storage I/O IBM Linux Technology Center